Arduous adj. 1. Demanding great effort or labor; difficult. “An arduousundertaking.” 2. Testing severely the powers of endurance; strenuous. “A long and arduous process.”

Antithesis n.pl. 1. Direct contrast; opposition. 2. The direct or exact opposite. “Hope is the antithesis of despair.”

A phrase in which two words of contradictory meaning are used together for special effect, for example, “wise fool” or “to make haste slowly.”

Pervicacious adj. Stubborn, extremely willful, obstinate. “He became quite pervicacious in his old age.”

Accoutrement n. Additional items of dress or equipment, carried or worn by a person or used for a particular activity. The General dressed for battle in shining accoutrements.”

Vernacular n. The language or dialect spoken by the ordinary people in a particular country or region. An idiomatic word, phrase, or expression. The idiom of a particular trade or profession: “In the legal vernacular.”

Paradigm n. A typical example or pattern of something; a model. “The economic paradigm was flawed.”

Deciduous adj. Not permanent or lasting; ephemeral. “The fire created a deciduous outlook for the company.”

Pedantic adj. 1. Characterized by a narrow, often ostentatious concern for book learning and formal rules. “A pedantic attention to details.”

Vexatious adj. 1. Full of annoyance or distress; harassed. 2. Causing or creating vexation; annoying. “Her ex-husband put her in a vexatioussituation.”